Validation Of Form With Layers

I've tested a very good validation script called(fValidate ). Now, I want it to implement into a php-form which has 2 layers. Layers are called with following code:

function showLayer(layer)
{
strHidden = ( !document.layers ) ? "hidden" : "hide";
strVisible = ( !document.layers ) ? "visible" : "show";

if( document.layers ){
lyrForm1 = document.idForm1;
lyrForm2 = document.idForm2;

} else if( document.getElementById ){

lyrForm1 = document.getElementById("idForm1").style;
lyrForm2 = document.getElementById("idForm2").style;

} else if( document.all ){

lyrForm1 = document.all["idForm1"].style;
lyrForm2 = document.all["idForm2"].style;
}

lyrForm1.visibility = (layer == "idForm1") ? strVisible : strHidden;
lyrForm2.visibility = (layer == "idForm2") ? strVisible : strHidden;

return false;
}

[<A HREF="javascript:void(0);" showLayer('idForm1');">page 1</A>]
[<A HREF="javascript:void(0);" showLayer('idForm2');">page 2</A>]
.

When I submit the form, the validation script alerts the first "wrong" field which is on layer 1 (invisible because the submit button is on layer 2). Normally it goes to that wrong field, but instead it submits the form...

Does anyone has any experience with validation of layered forms?

There is also the possibility of making a custom validation function. I could make use of it, but then... how does javascript know on which layer the wrong field is/was...?